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Possible World · Rigorous Reasoning · Rigorous Reasoning

Concept · Foundations

Possible World

A complete way things could consistently be, usually represented as a point in a model at which every proposition has a definite truth value.

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Why it matters

Possible worlds give modal talk a precise semantics and make box and diamond operators something you can actually compute over.

Where this shows up

Units and lessons using this concept

Following the links will take you to the page where this term is introduced in context.

Units (1)

Modal Logic: Necessity, Possibility, and CounterfactualsStudents learn to reason about necessity, possibility, and counterfactual conditionals using the box and diamond operators, possible-worl…

Lessons (3)

Capstone: Modal Reasoning in Philosophy and ScienceModal Logic: Necessity, Possibility, and Counterfactuals Counterfactuals and Possible WorldsModal Logic: Necessity, Possibility, and Counterfactuals What Is Modal Logic?Modal Logic: Necessity, Possibility, and Counterfactuals

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A, E, I, O Propositions Accessibility Relation Argument Atomic Statement Base Rate Bayes Factor Calibration Cardinality Cartesian Product Categorical Proposition Categorical Syllogism Circularity